Our object in summarising this discussion has been twofold: at once to note the existence of tics of extrinsic eye muscles, and to illustrate the intricacies of their diagnosis. A case not unlike the preceding, recorded by Noguès and Sirol,[72] was characterised by inability to look above a certain height without simultaneous raising of the head. Paralysis of the associated movements of elevation was excluded by the fact of the gradual onset, without an ictus, and by the absence of paralysis of convergence and of impairment of speech and intellect. Basing their conception of the case upon its post-febrile origin and the knowledge of hysterical antecedents, the authors were disposed to regard it as a neuropathic manifestation. It is conceivable that some cases of strabismus in children are nothing more than vicious habits transformed into tics, since, as a matter of fact, attentive supervision is frequently sufficient to effect a cure, although no doubt in other cases some visual abnormality is responsible for the condition. Finally, since accommodation is a function subservient to the will, tics of accommodation are theoretically possible. Our information thereanent must be sought from the ophthalmologists. We have met with genuine professional cramps of accommodation in those who use the microscope, as well as in opticians, watchmakers, etc. TICS OF THE NOSE--SNIFFING TICS The form these tics commonly take is a puckering of the nostrils to the more or less noisy accompaniment of a nasal inspiration or expiration, associated usually with curling of the upper lip. They are principally the sequel to some coryza, or inflammation, or some little nasal fissure or furuncle, and in their essence constitute a derangement of a complex functional act intended to ensure the dislodgment of any obstruction in the respiratory passages of the nose, in which act the muscles of inspiration or of expiration bilaterally co-operate. Where the contraction of the nose muscles is unilateral, it is generally part and parcel of a facial grimace confined to that side, and therefore an anomaly of mimicry. As for the pathogenic mechanism of the sniffing tic, it is simple enough. Some little passing obstacle in the air-ways, some minute, irritating sore, supply the occasion for an expiratory reaction, in the first instance, with wrinkling of the nose and dilatation of the nostrils, the repetition of which with each fresh sensation of discomfort or of pain speedily becomes automatic, and persists as a tic when mucus or abrasion has disappeared. So far from being obstinate, these tics are eminently amenable to treatment if they are uncomplicated. We have remarked on their occurrence, by the way, in the case of O. and his sister, in young J., in G., in the wife of S., etc. TICS OF THE LIPS--SUCKING TICS